Generally, an integrated circuit device such as a programmable logic device (PLD) may include digital and analog circuits. Examples of analog circuits include transceiver circuitry, voltage supply circuitry, filter circuitry, and mirroring circuits. Examples of digital circuits include programmable logic circuits and memory circuits.
A high-precision current mirror circuit, which generates an electrical current that is equal to a reference electrical current, may require matched active structures (e.g., transistor structures). Using a large number of dummy arrays may help to reduce manufacturing variations between the active structures so that a high-precision current mirror circuit may be formed. However, having a high number of dummy arrays may not be compatible with the latch-up rule (a design-for-manufacturing (DFM) requirement) for the active structures in the semiconductor circuit. The latch-up rule requires a well-tap structure to be formed within a relatively short distance (i.e., within 30 microns) from the active structures.
Although there are solutions to form a high-precision current mirror circuit such as placing well-tap structures between every two rows/columns of the active structures in the analog circuits, such solutions may generally increase the overall size of the integrated circuit and as such, are not preferable.